I used to fly with several guys who prided themselves on how light their planes were. One was Pat Tritle. They were all wood builders. Two liked scale planes more but another loved the old timers cause they had big wings and could be built very light.

Most of their planes would land at less than walking speed. Less than 5oz/sqft is what you are looking for.

So, I would recommend just about any old timer set of plans and just make it out of depron. You will have to be careful or it will be heavier than the balsa versions.

What is powering that airbus? I don't see anything like props or edf's. maybe it's just these old eyes.

If you are asking about the video in post #89 : you can see TINY props spinning inside the REAR portion of the nacelles , after it goes by the camera and you are viewing the rear of the plane ( about 33-34 seconds into the video ) . To make it easier to see , on the video's settings button : set it to HD and slow the video speed down to .25 .